DIFFERENTIAL EXPRESSION OF TRANSFORMING GROWTH-FACTOR-ALPHA AND INSULIN-LIKE GROWTH-FACTOR-II IN CHRONIC ACTIVE HEPATITIS-B, CIRRHOSIS AND HEPATOCELLULAR-CARCINOMA

In the present study we investigated the expression of transforming gr owth factor alpha and insulin-like growth factor II to explain the rol e of these growth factors in the development of hepatocellular carcino ma from chronic active hepatitis B and cirrhosis, The expression of tr ansforming growth factor alpha and insulin-like growth factor II was t ested in 38 tissue samples from patients with chronic active hepatitis B, 32 cirrhosis and 31 hepatocellular carcinoma, by immunohistochemic al staining using monoclonal anti-transforming growth factor alpha and anti-insulin-like growth factor II, All patients were seropositive fo r HBsAg. Transforming growth factor alpha was expressed in 26 (68.4%) of 38 chronic active hepatitis B, 18 (56.3%) of 32 cirrhosis and 16 (5 1.6%) of 31 hepatocellular carcinoma tissue samples, Transforming grow th factor alpha was found in the periportal hepatocytes of chronic act ive hepatitis B and in regenerating hepatocytes of cirrhotic nodules, In hepatocellular carcinoma tissues, transforming growth factor alpha- containing tumor cells were evenly distributed within the tumor tissue s but focal distribution limited to a part of tumor tissues was also o bserved, The expression of insulin-like growth factor II was observed in 30 (93.8%) of 32 cirrhosis and all the 31 hepatocellular carcinoma tissue samples tested, but not in chronic active hepatitis B samples, Insulin-like growth factor Il was expressed in most hepatocytes of reg enerating nodules and in tumorous as well as non-tumorous hepatocytes of hepatocellular carcinoma tissues, The current study indicates that, although enhanced expression of transforming growth factor alpha and insulin-like growth factor II in chronic liver diseases may function i n concert in multiple steps of hepatocarcinogenesis, insulinlike growt h factor II may play a more predominant role than transforming growth factor alpha in hepatocyte proliferation in regenerating nodules and i n tumor cell proliferation in hepatocellular carcinoma tissues.